package com.sky.interceptor;

import com.sky.constant.JwtClaimsConstant;
import com.sky.constant.MessageConstant;
import com.sky.context.BaseContext;
import com.sky.exception.LoginFailedException;
import com.sky.properties.JwtProperties;
import com.sky.utils.JwtUtil;
import io.jsonwebtoken.Claims;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * jwt令牌校验的拦截器
 */
@Component//拦截器是Spring框架提供的需要交给IOC容器管理
@Slf4j
public class JwtTokenUserInterceptor implements HandlerInterceptor {

    @Autowired
    private JwtProperties jwtProperties;

    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        //判断当前拦截到的是Controller的方法还是其他资源
        if (!(handler instanceof HandlerMethod)) {
            //当前拦截到的不是动态方法，直接放行
            return true;
        }

        //1、从请求头中获取令牌
        String token = request.getHeader(jwtProperties.getUserTokenName());
        if(!StringUtils.hasLength(token)){
            throw new LoginFailedException(MessageConstant.USER_NOT_LOGIN);
        }
        //2、校验令牌
        try {
            log.info("jwt校验:{}", token);
            Claims claims = JwtUtil.parseJWT(jwtProperties.getUserSecretKey(), token);
            Long UserId = Long.valueOf(claims.get(JwtClaimsConstant.USER_ID).toString());
            BaseContext.setCurrentId(UserId);
            log.info("当前员工id：{}", UserId);
            //3、通过，放行
            return true;
        } catch (Exception ex) {
            //4、不通过，响应401状态码
            response.setStatus(401);
            throw new LoginFailedException(MessageConstant.USER_NOT_LOGIN);
        }
    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        // 请求结束，清理线程变量中的 empId
        BaseContext.removeCurrentId();
    }

}
